JP2007040888A - Time display and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a time display and its control method, capable of avoiding erroneous time indication due to lack of remaining power of battery and the like. <P>SOLUTION: In the case that a battery voltage is continuously over a first threshold L1 (step S1:YES) the month, the hour and minute are indicated on a display panel, having indication sustainability (step S2). When the battery voltage lies continuously less than the first threshold L1 (step S1:NO), so that the hour and the minute are controlled to be non-indicated and an indicator that indicates insufficient remaining battery is shown (step S4, S5). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a time display device that displays time on a display unit having display holdability, and a control method therefor.

In recent years, there has been proposed a phenomenon in which charged particles dispersed in a liquid migrate by applying an electric field, that is, a timepiece using an electrophoretic display panel using the electrophoretic phenomenon (see, for example, Patent Documents 1 and 2). Since this type of display panel has a display retention property that retains display contents even when power is not supplied, the time can be continuously displayed even when driven.
JP-A-1-86116 JP 2005-84343 A

  However, in the above clock, when the remaining time of the battery is insufficient and the display time cannot be updated, the time at that time is still displayed due to the display holdability of the display panel, and the wrong time is continuously displayed. There was a problem.

  The present invention has been made in view of the above-described circumstances, and it is an object of the present invention to provide a time display device capable of avoiding an erroneous time display due to insufficient remaining power of a battery or the like and a control method thereof.

  In order to solve the above-described problems, the present invention includes a power source that supplies operating power and a display unit that is driven by the power from the power source and has display retention properties that retain display contents. In the time display device for displaying the power, the remaining amount estimating means for estimating the remaining amount of the power supply, and the control means for controlling the time information to be hidden when the estimated remaining amount of the power supply falls below a preset threshold value; It is characterized by providing. According to the present invention, when the estimated remaining amount of the power source falls below a preset threshold, the time information is controlled to be hidden. Therefore, the time information is hidden before the display can be rewritten due to a shortage of the remaining amount of the power source. Display can be controlled, and display of an incorrect time can be avoided.

In the above configuration, the control unit may control the time information to be hidden when a state where the estimated remaining amount of the power source is lower than the threshold value continues for a predetermined period. According to this configuration, for example, it is possible to avoid the case where the time information is controlled to be hidden when the remaining amount of the power supply temporarily decreases due to driving of the buzzer or the like, and the actual remaining amount of the power supply falls below the threshold value. The time information can be controlled so as not to be displayed only when it is detected.
In each of the above configurations, the control means may display information about the power source when the time information is controlled to be hidden. According to this configuration, it is possible to notify the user of power supply information at a timing when the remaining amount of the power supply decreases.

In each of the above configurations, when the control means controls the time information to be hidden, the time counting operation is continued, and when the remaining amount of the power source exceeds a preset threshold, the time based on the time counting operation is determined. Information may be displayed. According to this configuration, accurate time information can be displayed when the remaining amount of power increases.
Further, in each of the above-described configurations, the time information includes a plurality of time information with different update intervals, and the control means has a short update interval among the time information being displayed as the estimated remaining power of the power source decreases. The display information may be controlled to be hidden in order from the time information, and the rewrite interval of the display unit may be changed to the update interval of the time information having the shortest update interval among the time information being displayed. According to this configuration, it is possible to reduce power consumption while displaying accurate time information. In each of the above configurations, the display unit may include an electrophoretic display panel.

  The present invention also includes a power source that supplies operating power and a display unit that is driven by the power from the power source and has a display retention property that retains display contents, and displays time information on the display unit. In the apparatus control method, the remaining amount of power is estimated, and when the estimated remaining amount of power falls below a preset threshold, time information is controlled to be hidden. According to the present invention, when the estimated remaining amount of the power source falls below a preset threshold, the time information is controlled to be hidden. Therefore, the time information is hidden before the display can be rewritten due to a shortage of the remaining amount of the power source. Display can be controlled, and display of an incorrect time can be avoided.

  Since the present invention estimates the remaining amount of power and controls the time information to be hidden when the estimated remaining amount of power falls below a preset threshold, the display can be rewritten due to insufficient power remaining. The time information can be controlled to be hidden before it disappears, and the display of an incorrect time can be avoided.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing an external configuration of a wristwatch 1 according to the present embodiment. As shown in this figure, the wristwatch 1 includes a watch case 2 and a pair of watch bands 3 attached to the watch case 2 and wound around the wrist of the user. The watch case 2 has a time display window 4 for displaying the time on the front, and a display panel 5 for displaying the time is visible from the time display window 4. Further, the time display window 4 is fitted with a cover body 6 made of transparent resin, transparent glass or the like, and the display panel 5 is protected by the cover body 6. Further, the watch case 2 is provided with a buzzer 7 and operation buttons 8 for various operations such as time correction.

  The display panel 5 displays a time display segment 5A for displaying the hour and minute (four-digit number and colon), and a month and day display for displaying the month and day (four-digit number and slash). Segment section 5B and a segment section 5C for displaying an indicator indicating that the remaining battery level is low.

A time display unit 10 configured integrally with the display panel 5 is disposed in the watch case 2, and the time display unit 10 includes a circuit board 11A and a display as shown in a sectional view in FIG. A frame 11B, a display substrate 11C, a transparent substrate 11D, and a circuit holder 13 for holding them are provided.
The display substrate 11C is provided with a segment electrode 14 corresponding to each segment of the segment portions 5A to 5C and a common electrode segment electrode 15 on the upper surface thereof.
A circuit board 11A is arranged on the lower surface of the display board 11C via a display frame 11B, and the elements 16 constituting the display drive circuit 40, the control unit 50, and the like are mounted on the circuit board 11A. A contact 11A1 wired to the element 16 (display drive circuit 40) is provided on the upper surface of the circuit board 11A, and a contact connected to the electrodes 14 and 15 on the lower surface of the display board 11C. 11C1 is provided, and these contacts 11A1 and 11C1 are electrically connected via a connection connector 17 that penetrates the display frame 11B.

Further, a switch electrode 18 is provided on the side surface of the circuit board 11A, and the switch electrode 18 is configured to be conductive through a leaf spring 19 provided on the circuit holder 13, and the leaf spring 19 is configured as described above. When it is deformed by the pressing operation of the operation button 8, it conducts through the deformed leaf spring 19. This conduction / non-conduction is detected by the element 16 (the control unit 50 in this embodiment).
A battery (power source) 20 for supplying driving power to the element 16 is detachably provided on the lower surface of the circuit board 11A. Further, a circuit frame 21 covering the element 16 is fixed to the circuit board 11A, and the element 16 is protected by the circuit frame 21. The battery 20 is a button battery that is a primary battery.

  The transparent substrate 11D is provided with a transparent common electrode 25 formed by ITO (Indium-Tin Oxide) deposition or the like on the surface of the display substrate 11C, and the transparent common electrode 25 and the segment electrode 14 of the display substrate 11C. The electrophoretic layer 30 is provided between the transparent common electrode 25 and the common electrode segment electrode 15. The common electrode conductive material 26 is interposed between the transparent common electrode 25 and the common electrode segment electrode 15. The conductive material 26 for the common electrode is formed of, for example, conductive rubber, and the conductive rubber is deformed in accordance with the gap between the common electrode 25 and the common electrode segment electrode 15, so that these electrodes 25, The continuity between 15 is reliably ensured.

As shown in FIG. 3, the electrophoretic layer 30 includes a plurality of microcapsules 31, and an electrophoretic dispersion liquid 33 in which electrophoretic particles 32 are mixed is enclosed in the microcapsules 31. For example, blue particles charged to a positive polarity are applied to the electrophoretic particles 32, and the electrophoretic dispersion liquid 33 is colored white, so that a so-called one-particle electrophoretic layer is formed.
Accordingly, the common electrode segment electrode 15 (FIG. 2) is held at 0 V potential (ground potential) by the display drive circuit 40, the common electrode 25 is set to 0 V potential, and a positive drive voltage is applied to the predetermined segment electrode 14. Is supplied to a positive potential, an electric field from the segment electrode 14 toward the common electrode 25 is generated, and the positively charged electrophoretic particles (blue particles) 32 in the microcapsule 31 move to the common electrode 25 side. Along with this, the white electrophoretic dispersion liquid 33 moves to the segment electrode 14 side. As a result, since the microcapsule 31 visually recognized from the transparent substrate 11D side exhibits blue, the segment displays blue.

On the other hand, a positive drive voltage is supplied to the common electrode segment electrode 15 by the display drive circuit 40 to set the common electrode 25 to a positive potential, and the predetermined segment electrode 14 is held at a 0 V potential. In this case, the positively charged electrophoretic particles (blue particles) 32 move to the segment electrode 14 side, and accordingly, the white electrophoretic dispersion liquid 33 moves to the common electrode 25 side. The microcapsule 31 visually recognized from the transparent substrate 11D side exhibits white, and the segment displays white. In addition, when no potential difference is generated between the common electrode 25 and the segment electrode 14, the electrophoretic particles (blue particles) 32 do not move, so the display color of the segment remains unchanged and the previous state is maintained. Is done.
In the present embodiment, the display drive circuit 40 has a built-in booster circuit, boosts a voltage (eg, 3V) supplied from the power supply 20 to generate a + 12V voltage, and this + 12V voltage or 0V Is applied to the segment electrode 14 and the common electrode 25 as a drive voltage.

FIG. 4 shows the electrical configuration of the time display unit 10.
The control unit 50 is connected to the display drive circuit 40 and the battery 20 via a pattern wiring provided on the display substrate 11C. The control unit 50 includes a time measuring circuit 51, an input / output circuit (I / O) 52, A voltage control circuit 53, an operation control circuit 54, a buzzer drive circuit 55, a low voltage detection circuit 56, and a control circuit (control means) 57 are provided.
The timer circuit 51 measures the date and time (hours and minutes) by counting the oscillation pulses of an oscillation circuit (not shown). The timer circuit 51 is connected to the display drive circuit 40 via the input / output circuit 52. Connected with.
The voltage control circuit 53 supplies power supplied from the battery 20 to each part in the control unit 50 and the display drive circuit 40, and the operation control circuit 54 conducts / non-conducts the switch electrode 18. Is detected, and the operation of the operation button 8 is detected, and the detection result is notified to the control circuit 57. The buzzer drive circuit 55 drives the buzzer 7 under the control of the control circuit 57 to emit a buzzer sound.

The low voltage detection circuit (remaining amount estimating means) 56 detects the voltage of the battery 20 and estimates the remaining amount of the battery 20 from the detected voltage. More specifically, the battery 20 is a battery of 3V battery. In this case, whether or not the voltage of the battery 20 is equal to or higher than a first threshold value L1 (for example, 2.8V) set to a value larger than the lower limit value of the voltage range in which display can be rewritten by the display drive circuit 40, and It is determined whether or not it is equal to or higher than a second threshold value L2 (for example, 2.7 V) set to a value that substantially coincides with the lower limit value of the voltage range, and the determination result is notified to the control circuit 57.
The control circuit 57 centrally controls the time display unit 10 as a whole. The control circuit 57 includes a CPU, a ROM, a RAM, and the like. When the CPU executes a control program stored in the ROM, the control unit 57 50 controls the operation of each unit and outputs various instructions to the display drive circuit 40 via the input / output unit (I / O) 52. As this instruction, there are an instruction of a display object (“month and day”, “hour and minute”, “indicator”), an instruction of a rewrite interval, and the like.

  As described above, the display drive circuit 40 is a circuit that drives the display panel 5, acquires time information including the date, time, and time counted by the time measuring circuit 51 under the instruction of the control circuit 57, and The rewriting process is performed at the rewriting interval, and time information and an indicator are displayed on the display panel 5.

  By the way, the control circuit 57 executes display change processing for changing the display at a predetermined interrupt cycle based on the determination result of the low voltage detection circuit 56. The display change process will be described below with reference to the flowchart shown in FIG. In the initial state, the display drive circuit 40 displays both “month and day” and “hour and minute” on the display panel 5, and “month and day” and “hour and minute” of the display panel 5 at the update timing of minutes. Rewriting process is performed.

In this display change process, the control circuit 57 first determines whether or not the voltage of the battery 20 is continuously equal to or higher than the first threshold L1 by the low voltage detection circuit 56 (step S1). In this case, the control circuit 57 determines whether or not the determination result is maintained for a predetermined period. Only when the determination result is maintained for a predetermined period, the control circuit 57 proceeds to the subsequent process (the process of step S2 or S3). If not maintained, the process of step S1 is repeated at a predetermined cycle. As a result, even if the battery voltage temporarily decreases during driving of the buzzer 7 or the like, the determination result based on the decreased battery voltage becomes invalid, and an accurate determination result based on the normal voltage value of the battery 20 can be acquired. It becomes possible.
When the battery voltage is equal to or higher than the first threshold value L1 (step S1: YES), the control circuit 57 causes the display drive circuit 40 to display “month / day” and “hour / minute” on the display panel 5 (step S2). . Thus, when the remaining battery level is sufficient, the first display state in which both “month and day” and “hour and minute” are displayed is maintained. In this display state, the display drive circuit 40 executes the rewriting process of the display panel 5 at the update interval of minutes, so that the display time and the like are updated at a timing that matches the update of the time.

On the other hand, when the battery voltage is equal to or lower than the first threshold L1 (step S1: NO), the control circuit 57 determines whether or not the voltage of the battery 20 is continuously equal to or higher than the second threshold L2 by the low voltage detection circuit 56 ( Step 3). In this case, as in step S1, the control circuit 57 determines whether or not the determination result is maintained for a predetermined period. Only when the determination result is maintained for a predetermined period, the control circuit 57 proceeds to subsequent processing. If the determination result is not maintained, the process of step S3 is repeated. If the determination result is not maintained, the process may proceed to step S1. Thereby, a comparison result between the normal voltage value of the battery 20 and the second threshold value L2 can be acquired.
When the battery voltage is equal to or higher than the second threshold L2 (step S3: YES), the control circuit 57 causes the display drive circuit 40 to display “month / day” and “indicator” on the display panel 5 (step S4). In the second display state, the display drive circuit 40 executes the rewriting process of the display panel 5 at the day update interval, so that the display is displayed at the timing of the day update (for example, the timing at 0 o'clock). The date is updated. That is, the rewriting process of the display panel 5 is executed at the update interval of the information (day) when the update interval is the shortest among the information (month / day) regarding the display time. Thereby, compared with the 1st display state which displays time and minute, the frequency | count of rewriting of the display panel 5 per predetermined time can be reduced significantly, and power consumption can be reduced.
In addition, by displaying an indicator (see FIG. 1) indicating that the remaining battery level is low, the user can be notified that the remaining battery level is low, and the user can recognize that the display of only the date is not a failure of the watch 1. be able to.

  When the second threshold value L2 or less (step S3: NO), that is, when the remaining amount of the battery 20 is almost exhausted, the control circuit 57 displays only the “indicator” on the display panel 5 by the display drive circuit 40. Let In the third display state, the rewriting process of the display panel 5 is performed only once, and the indicator is continuously displayed by holding the display of the display panel 5. For this reason, the power consumption can be further reduced as compared with the case of the second display state because the rewriting process is completed only once. In this case, since the indicator is displayed even when the battery is dead, it is possible to prompt the user to replace the battery and to make the user recognize that the watch 1 is not out of order.

As described above, according to the present embodiment, when the remaining amount of the battery 20 decreases, the time information (month day and hour and minute) is controlled to be hidden, so that the time information is displayed on the display panel 5 having display retainability. Even if is displayed, the time information can be hidden before the display can be rewritten due to insufficient remaining battery 20, and the wrong time or date is still displayed. Can be reliably avoided.
Further, in the present embodiment, as the remaining amount of the battery 20 decreases, the information is hidden in order from the time when the update interval is short, and the update interval of the display panel 5 is the shortest among the time information being displayed. Since the time information is changed to the update interval, power consumption can be reduced and driving time can be extended while displaying accurate time information.

The above-described embodiment is merely one aspect of the present invention, and can be arbitrarily modified within the scope of the present invention. For example, in the above-described embodiment, the case where the primary battery is applied to the battery 5 has been described. However, a secondary battery may be applied to this type of power source. In addition, when a secondary battery is applied, a power generation device that performs solar power generation or thermal power generation may be provided, and the secondary battery may be configured to be rechargeable by the generated power of the power generation device.
In such a configuration that can be charged, the remaining amount of the secondary battery may increase due to charging, so by executing the display change process, the second battery is increased according to the increase in the voltage of the secondary battery. 3 display state → second display state → first display state is changed, and display / non-display of time information can be variably controlled according to the remaining amount of the secondary battery. In addition, in this case, since the timing operation by the timing circuit 51 is continued, it is possible to display the accurate time and month / day based on the timing operation when switching the time and month / day from display to non-display. It is.

Further, in the above embodiment, the case where the clock 1 can display the date and time is exemplified, but the present invention is not limited to this, and a year and a second may be displayed, and a calendar such as a date is displayed. May be configured such that only the time can be displayed. In a case where only the time can be displayed, it is determined whether or not the voltage of the power source is, for example, the first threshold L1 or more. If the voltage is more than the first threshold L1, the time is displayed and is less than the first threshold L1. In such a case, the time may be hidden and the indicator may be displayed. In addition, the indicator is not limited to a picture, but may be a character. In short, it may be any indicator that shows information on the power source.
In the above-described embodiment, the case where a one-particle electrophoretic display panel is applied as the display panel 5 having display holding properties is exemplified. However, the present invention is not limited to this, and the electrophoretic display panel such as a two-particle system, twist A display panel having display holding properties such as a ball type display panel, an electrochromic display panel, and a ferroelectric liquid crystal panel can be widely applied. The display method is not limited to the segment method, and a dot matrix method may be applied.
Further, in the above-described embodiment, the case where the present invention is applied to a wristwatch has been described. It can be widely applied to a device).

It is a figure which shows the external appearance of the wristwatch which concerns on one Embodiment of this invention. It is sectional drawing which shows typically the time display unit of a wristwatch. It is sectional drawing which shows the structure of a display panel. It is a block diagram which shows the electric constitution of a time display unit. It is a flowchart which shows operation | movement of a time display unit.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Wristwatch, 5 ... Display panel, 10 ... Time display unit, 11A ... Circuit board, 11B ... Display frame, 11C ... Display board, 11D ... Transparent substrate, 12 ... Transparent substrate, 14 ... Segment electrode, 17 ... Connection connector, DESCRIPTION OF SYMBOLS 20 ... Battery (power supply), 25 ... Common electrode, 26 ... Conducting material for common electrodes, 30 ... Electrophoresis layer, 31 ... Microcapsule, 40 ... Display drive circuit, 50 ... Control part, 51 ... Timing circuit, 52 ... On Output circuit 53 ... Voltage control circuit 54 ... Operation control circuit 55 ... Buzzer drive circuit 56 ... Low voltage detection circuit 57 ... Control circuit (control means)

Claims (7)

In a time display device that includes a power source that supplies operating power, and a display unit that is driven by the power from the power source and has display retention properties that retain display content, and displays time information on the display unit.
A remaining amount estimating means for estimating the remaining amount of the power source;
And a control means for controlling the time information to be hidden when the estimated remaining amount of the power source falls below a preset threshold value. 2. The time display device according to claim 1, wherein the control unit controls the time information to be hidden when a state where the estimated remaining amount of the power source is lower than the threshold value continues for a predetermined period. 3. The time display device according to claim 1, wherein when the time information is controlled to be non-displayed, the control unit displays information related to the power source. 4. When the time information is controlled to be hidden, the control means continues the time counting operation, and displays the time information based on the time counting operation when the remaining amount of the power source exceeds a preset threshold value. The time display device according to any one of claims 1 to 3. The time information includes a plurality of time information with different update intervals, and the control means hides the displayed time information from the time information with the shortest update interval in accordance with a decrease in the estimated remaining power of the power source. 5. The time display according to claim 1, wherein the rewriting interval of the display unit is changed to an update interval of information when the update interval is shortest among time information being displayed. apparatus. The time display device according to claim 1, wherein the display unit includes an electrophoretic display panel. In a control method of a time display device comprising: a power source that supplies operating power; and a display unit that is driven by power from the power source and has a display retention property that retains display content, and displays time information on the display unit.
A method for controlling a time display device, wherein the remaining amount of power is estimated, and when the estimated remaining amount of power falls below a preset threshold, time information is controlled to be hidden.

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